Experts
The results of a 20-year research project are described in Expert Political Judgment: How Good is It? How Can We Know?. The idea was to solicit thousands of predictions from hundreds of experts about the fates of dozens of countries, and then score the predictions for accuracy.
Boom and doom pundits are the most reliable over-claimers.
Between 1985 and 2005, boomsters made 10-year forecasts that exaggerated the chances of big positive changes in both financial markets (e.g., a Dow Jones Industrial Average of 36,000) and world politics (e.g., tranquility in the Middle East and dynamic growth in sub-Saharan Africa). They assigned probabilities of 65% to rosy scenarios that materialized only 15% of the time.
In the same period, doomsters performed even more poorly, exaggerating the chances of negative changes in all the same places where boomsters accentuated the positive, plus several more (e.g., the disintegration of Canada, Nigeria, India, Indonesia, South Africa, Belgium, and Sudan). They assigned probabilities of 70% to bleak scenarios that materialized only 12% of the time.
Over-claimers rarely paid penalties for being wrong. Indeed, the media showered lavish attention on over-claimers while neglecting their humbler colleagues.
Following Isaiah Berlin, we classify experts as “hedgehogs” or “foxes.” Hedgehogs are big-idea thinkers in love with grand theories: libertarianism, Marxism, environmentalism, etc.
Hedgehogs don’t know when to make concessions to other points of view. They take their theories too seriously. They make more mistakes, but they get more attention.
Foxes are better at curbing their ideological enthusiasms. They are comfortable with protracted uncertainty about who is right even in bitter debates, conceding gaps in their knowledge and granting legitimacy to opposing views. They sprinkle their conversations with linguistic qualifiers that limit the reach of their arguments: “but,” “however,” “although.”
Foxes make fewer mistakes. They will often agree with hedgehogs up to a point, before complicating things.
Foxes balance conflicting arguments and often conclude that the likeliest outcome is more of the same.